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      <details id="toc" open><summary>Table of contents</summary><ul>
<li><a href="#documentation_about_this_documentation">About this documentation</a>
<ul>
<li><a href="#documentation_contributing">Contributing</a></li>
<li><a href="#documentation_stability_index">Stability index</a></li>
<li><a href="#documentation_stability_overview">Stability overview</a></li>
<li><a href="#documentation_json_output">JSON output</a></li>
<li><a href="#documentation_system_calls_and_man_pages">System calls and man pages</a></li>
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      <div id="apicontent">
        <h2>About this documentation<span><a class="mark" href="#documentation_about_this_documentation" id="documentation_about_this_documentation">#</a></span></h2>


<p>Welcome to the official API reference documentation for Node.js!</p>
<p>Node.js is a JavaScript runtime built on the <a href="https://v8.dev/">V8 JavaScript engine</a>.</p>
<section><h3>Contributing<span><a class="mark" href="#documentation_contributing" id="documentation_contributing">#</a></span></h3>
<p>Report errors in this documentation in <a href="https://github.com/nodejs/node/issues/new">the issue tracker</a>. See
<a href="https://github.com/nodejs/node/blob/HEAD/CONTRIBUTING.md">the contributing guide</a> for directions on how to submit pull requests.</p>
</section><section><h3>Stability index<span><a class="mark" href="#documentation_stability_index" id="documentation_stability_index">#</a></span></h3>

<p>Throughout the documentation are indications of a section's stability. Some APIs
are so proven and so relied upon that they are unlikely to ever change at all.
Others are brand new and experimental, or known to be hazardous.</p>
<p>The stability indices are as follows:</p>
<p></p><div class="api_stability api_stability_0">Stability: 0 - Deprecated. The feature may emit warnings. Backward
compatibility is not guaranteed.</div><p></p>
<!-- separator -->
<p></p><div class="api_stability api_stability_1">Stability: 1 - Experimental. The feature is not subject to
<a href="https://semver.org/">Semantic Versioning</a> rules. Non-backward compatible changes or removal may
occur in any future release. Use of the feature is not recommended in
production environments.</div><p></p>
<!-- separator -->
<p></p><div class="api_stability api_stability_2">Stability: 2 - Stable. Compatibility with the npm ecosystem is a high
priority.</div><p></p>
<!-- separator -->
<p></p><div class="api_stability api_stability_3">Stability: 3 - Legacy. The feature is no longer recommended for use. While it
likely will not be removed, and is still covered by semantic-versioning
guarantees, use of the feature should be avoided.</div><p></p>
<p>Use caution when making use of Experimental features, particularly within
modules. Users may not be aware that experimental features are being used.
Bugs or behavior changes may surprise users when Experimental API
modifications occur. To avoid surprises, use of an Experimental feature may need
a command-line flag. Experimental features may also emit a <a href="process.html#process_event_warning">warning</a>.</p>
</section><section><h3>Stability overview<span><a class="mark" href="#documentation_stability_overview" id="documentation_stability_overview">#</a></span></h3>
<!-- STABILITY_OVERVIEW_SLOT_BEGIN --><table><thead><tr><th>API</th><th>Stability</th></tr></thead><tbody><tr><td class="module_stability"><a href="assert.html">assert</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="async_hooks.html">async_hooks</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="buffer.html">buffer</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="child_process.html">child_process</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="cluster.html">cluster</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="console.html">console</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="crypto.html">crypto</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="dgram.html">dgram</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="diagnostics_channel.html">diagnostics_channel</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="dns.html">dns</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="domain.html">domain</a></td><td class="api_stability api_stability_0">(0) Deprecated</td></tr><tr><td class="module_stability"><a href="fs.html">fs</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="http.html">http</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="http2.html">http/2</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="https.html">https</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="inspector.html">inspector</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="modules.html">module</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="os.html">os</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="path.html">path</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="perf_hooks.html">performance_measurement_apis</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="punycode.html">punycode</a></td><td class="api_stability api_stability_0">(0) Deprecated</td></tr><tr><td class="module_stability"><a href="querystring.html">querystring</a></td><td class="api_stability api_stability_3">(3) Legacy</td></tr><tr><td class="module_stability"><a href="readline.html">readline</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="repl.html">repl</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="stream.html">stream</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="string_decoder.html">string_decoder</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="timers.html">timers</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="tls.html">tls_(ssl)</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="tracing.html">trace_events</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="tty.html">tty</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="url.html">url</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="util.html">util</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="vm.html">vm</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="wasi.html">webassembly_system_interface_(wasi)</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="worker_threads.html">worker_threads</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="zlib.html">zlib</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr></tbody></table><!-- STABILITY_OVERVIEW_SLOT_END -->
</section><section><h3>JSON output<span><a class="mark" href="#documentation_json_output" id="documentation_json_output">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.6.12</span>
</div>
<p>Every <code>.html</code> document has a corresponding <code>.json</code> document. This is for IDEs
and other utilities that consume the documentation.</p>
</section><section><h3>System calls and man pages<span><a class="mark" href="#documentation_system_calls_and_man_pages" id="documentation_system_calls_and_man_pages">#</a></span></h3>
<p>Node.js functions which wrap a system call will document that. The docs link
to the corresponding man pages which describe how the system call works.</p>
<p>Most Unix system calls have Windows analogues. Still, behavior differences may
be unavoidable.</p></section>
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